[Au]/[Ag]-Catalyzed Glycosidation of Ethynylcyclohexyl Glycosyl Carbonates Enables Direct Stereoselective Synthesis of 2-Azido-2-deoxy-β-mannopyranosides.

We describe the [Au]/[Ag]-catalyzed activation of ethynylcyclohexyl 2-azido-4,6--benzylidene mannosyl carbonates for β-mannosamine linkage preparation in high yield and selectivity in a temperature- and concentration-dependent manner. VT-NMR studies reveal an anomeric triflate intermediate generated in the absence of an acceptor alcohol that is stable up to -10 °C. The generality of the protocol was illustrated by successful application to a series of acceptors and by synthesis of a fully protected type 19F capsular trisaccharide.

C2-Linked Arabinose-Functionalized Polystyrene Microbeads Selectively Target .

Carbohydrates play pivotal roles in the first stages of microbial infections and can be exploited as decoys to hijack the interactions between bacteria and the host cell. Multivalent glycan probes mimicking the natural presentation of glycans in living cells have been successfully employed to study fundamental carbohydrate/protein interactions in microbial systems; however, most pathogenic glycan receptors exhibit a shared specificity for commonly found sugars present in both healthy and pathogenic cells, posing a challenge for target selectivity. In this study, we report the synthesis of a small library of d-arabinose multivalent probes, a sugar absent in human physiology, and their evaluation in a bacteria agglutination assay using cluster analysis.

[Au]/[Ag]-catalysed synthesis of non-hydrolysable -glycosides.

Many -glycosides are found in natural products, drugs and small molecular probes. Herein, we report the synthesis of -glycosides by the [Au]/[Ag]-catalysed activation of ethynylcyclohexyl glycosyl carbonate donors. This mild, catalytic, fast and high yielding protocol enables the synthesis of a diverse array of -glycosides that were otherwise challenging to synthesize.

Total Synthesis of Conjugation-Ready Hyperbranched Pentasaccharide of VKM Ac-2641 by [Au]/[Ag] Catalysis.

Infections by spp. cause an economic burden to farmers. The components present in the cell wall glycopolymers (CWGs) are important for studying the host-pathogen interactions, colonization, and infection.